JP4168332B2 - SEALING DEVICE AND SCROLL TYPE FLUID MACHINE USING THE SEALING DEVICE - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sealing device provided between sliding surfaces and provided at a location where a high-pressure side fluid and a low-pressure side fluid are blocked, and for example, relates to a sealing device suitably used for a scroll fluid machine.
[0002]
[Prior art]
In general, a scroll fluid machine is provided with a casing, a fixed scroll provided in the casing, a drive shaft rotatably provided in the casing, and a swingable shaft provided on the drive shaft in the casing. 2. Description of the Related Art A scroll scroll that is in sliding contact with a scroll in a collision state and a plurality of compression chambers defined between the swing scroll and a fixed scroll are known.
[0003]
In recent years, in order to increase the amount of compressed air, the following configuration is known (Patent Document 1).
[0004]
That is, the scroll-type fluid machine according to this prior art is provided with first and second fixed scrolls spaced apart in the axial direction of the casing, and the end plate has a spiral shape so as to face the first and second fixed scrolls. It is set as the structure provided with the said 1st, 2nd turning scroll by which the lap | wrap part of this was erected.
[0005]
By the way, when the scroll type fluid machine of the above-described prior art is used as a two-stage compressor, the fixed scroll discharge port serving as the low pressure side and the suction of the fixed scroll serving as the high pressure side among the first and second fixed scrolls. High pressure compressed air compressed in two stages by connecting the compressed air compressed between the fixed scroll on the low pressure side and the orbiting scroll between the fixed scroll on the high pressure side and the orbiting scroll. Is stored in a tank or the like.
[0006]
However, in such a two-stage scroll type fluid machine, the compression chamber on the outermost peripheral side of the high-pressure side has a pressure higher than the atmospheric pressure. There exists a possibility that it may leak, and there exists a problem that compression efficiency cannot be improved.
[0007]
In order to solve such problems, it is conceivable to use a seal (contact seal) as shown in the scroll compressor shown in Patent Document 2. This seal is a resin seal ring having a substantially U-shaped cross-section with an inner diameter side opened in a groove on the outer peripheral side of the end plate of the orbiting scroll so that the internal compressed fluid does not leak to the outside from the outermost compression chamber. Is provided. Further, a spring member is provided on the inner diameter side of the seal ring. This seal is provided with a minute gap between the sliding surfaces on the inner diameter side so that the compressed fluid in the compression chamber on the outermost peripheral side flows, and the seal ring and the spring member are opened by the compressed fluid. The sliding surface is pressed against the mating sliding surface.
[0008]
[Patent Document 1]
JP 2000-356193 A
[Patent Document 2]
JP 2002-081388 A
[0009]
[Problems to be solved by the invention]
However, although the above-mentioned problem is solved by using a seal as shown in Patent Document 2, the seal shown in Patent Document 2 has an average spring force set in advance, so Due to processing tolerances such as the thickness of the ring and the gap between the sliding surfaces, the seal ring may be pressed more than necessary against the mating surface. In this case, there is a problem that the sliding resistance increases.
[0010]
In addition, the pressing force on the mating surface of the seal ring is determined so that it will function well from the beginning of a new product. May cause problems such as loss of sliding resistance and a decrease in durability of the seal ring.
[0011]
The present invention has been made in view of the above-described problems of the prior art, and in a sealing device used between sliding surfaces defined on a high pressure side and a low pressure side, the sealing member is pressed against the mating sliding surface with an optimal pressing force. Accordingly, an object of the present invention is to provide a sealing device that has reduced sliding resistance and improved durability.
[0012]
[Means for Solving the Problems]
  To solve the above-mentioned problemsInvention of Claim 1Is provided between the one side member, the other side member disposed opposite to the one side member and sliding, and between the one side member and the other side member. A sealing device comprising: a groove provided on a sliding surface of the one-side member; a sealing member inserted into the groove; and provided between the sealing member and the groove; A first intrusion-blocking seal for blocking pressure intrusion, a second intrusion-blocking seal for blocking pressure intrusion on the low-pressure side, the first and second intrusion-blocking seals, the groove bottom side, and the A sealed chamber formed by a sealing member;A communication path provided in the seal member so as to communicate the sealing chamber side and the sliding surface side of the seal member, and the communication path is a high-pressure side end of the opening on the sliding part side The part is configured to move to the low pressure side according to the wear of the seal memberIt is to have done.
[0013]
In order to solve the above-described problem, the invention of claim 4 includes a one-side member, an other-side member arranged to face the one-side member and sliding, and the one-side member and the other-side member. A sealing device provided between the high pressure side and the low pressure side, the annular groove provided on the sliding surface of the one side member, and being fitted into the groove; An annular seal member sliding with the other side member;
A first intrusion blocking seal that is provided between the seal member and the groove and blocks the pressure intrusion on the high pressure side; a second intrusion blocking seal that blocks the pressure intrusion on the low pressure side; 1. A sealing chamber formed by the second intrusion blocking seal, the groove bottom side and the sealing member, and the sealing chamber side and sliding surface side of the sealing member are provided in the sealing member so as to communicate with each other. The communication path is provided with an inclined portion that is inclined from the high-pressure side to the low-pressure side from the sliding surface side to the sealed chamber.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a case where the sealing device of the present invention is applied to a scroll type air compressor will be described as an example, and will be described in detail with reference to FIGS.
[0025]
1 is a cylindrical casing that forms the outer frame of a scroll type air compressor. The casing 1 is fixed to a casing body 2 having an axis O1-O1 and both ends of the casing body 2 as shown in FIG. It is comprised by the left and right bearing attachment cylinder parts 3A and 3B. The bearing mounting cylinder portion 3A is composed of an annular portion 3A1 and a cylinder portion 3A2. Further, the bearing mounting cylinder part 3B is also constituted by an annular part 3B1 and a cylinder part 3B2.
[0026]
Reference numerals 4A and 4B denote first and second fixed scrolls fixedly provided at both ends of the casing 1, respectively. The first fixed scroll 4A is formed in a substantially disc shape and the center is the axis O1 of the casing 1. End plate 5A disposed so as to coincide with -O1, spiral wrap portion 6A standing on the surface of end plate 5A, and axial direction so as to surround wrap portion 6A from the outer peripheral side of end plate 5A And a flange portion 8A protruding radially outward from the outer peripheral side of the cylinder portion 7A.
[0027]
In the fixed scroll 4A, the flange portion 8A is integrally attached to the opening end of the cylindrical portion 3A2 of the bearing mounting cylindrical portion 3A via a bolt (not shown) or the like. The fixed scroll 4A is provided with a first suction port 9A located on the outer peripheral side thereof, and a first discharge port 10A is provided on the center side of the end plate 5A.
[0028]
The second fixed scroll 4B (other side member) is also provided with an end plate 5B, a wrap portion 6B, a cylinder portion 7B, a flange portion 8B, a second suction port 9B, and a second discharge port 10B.
[0029]
An electric motor 11 is provided between the fixed scrolls 4 </ b> A and 4 </ b> B and provided in the casing body 2. The electric motor 11 includes a stator 12 fixedly provided on the inner peripheral side of the casing main body 2, and the stator 12. The rotor 13 is rotatably arranged on the inner peripheral side. The axis of the stator 12 and the axis of the rotor 13 are arranged on the same axis as the axis O 1 -O 1 of the casing 1. The electric motor 11 drives the rotary shaft 14 by rotating the rotor 13.
[0030]
Reference numeral 14 denotes a rotating shaft that is rotatably provided between the annular portion 3A1 of the bearing mounting cylinder portion 3A and the annular portion 3B1 of the bearing mounting cylinder portion 3B, and constitutes an output shaft together with a turning shaft 15 described later. Is formed as a hollow shaft body and is inserted and provided on the inner peripheral side of the rotor 13 of the electric motor 11. The rotating shaft 14 is rotatably provided at both ends in the annular portions 3A1, 3B1 of the bearing mounting cylinder portions 3A, 3B.
[0031]
Reference numeral 15 denotes a revolving shaft provided between orbiting scrolls 17A and 17B, which will be described later. The revolving shaft 15 is formed as a solid cylindrical body on an eccentric axis O2-O2 eccentric from the axis O1-O1 by a dimension δ. Has been placed. Further, the turning shaft 15 has an intermediate portion in the axial direction as a large-diameter shaft portion 16, and both side portions in the axial direction as small-diameter shaft portions 16A and 16B. The small-diameter shaft portions 16 </ b> A and 16 </ b> B of the turning shaft 15 are rotatably supported on both end sides of the rotating shaft 14 and constitute an output shaft of the electric motor 11 together with the rotating shaft 14.
[0032]
Reference numerals 17A and 17B denote first and second orbiting scrolls which are provided in the casing 1 so as to be opposed to the fixed scroll 4A. The first orbiting scroll 17A and the first fixed scroll 4A are arranged on the low pressure side. It constitutes an air compressor. And the 1st turning scroll 17A is comprised by the end plate 18A, the spiral-shaped lap | wrap part 19A, etc. similarly to the 1st fixed scroll 4A.
[0033]
The orbiting scroll 17A is disposed so that the lap portion 19A overlaps the wrap portion 6A of the fixed scroll 4A by a predetermined angle (for example, 180 degrees), and a plurality of compression chambers are provided between the wrap portions 6A and 19A. 20A is defined.
[0034]
Further, the orbiting scroll 17A is provided with a boss portion 21A located at the center of the back surface thereof. A small-diameter shaft portion 16A of the pivot shaft 15 is fixedly attached to the boss portion 21A by press-fitting or bolting.
[0035]
The second orbiting scroll 17B (one side member) forms a high-pressure side air compressor together with the second fixed scroll 4B. The second orbiting scroll 17B is also roughly constituted by an end plate 18B, a lap portion 19B, and a boss portion 21B. In the boss portion 21B, a small-diameter shaft portion 16B of the orbiting shaft 15 is press-fitted or bolted. It is fixedly installed.
[0036]
Further, the second orbiting scroll 17B defines a plurality of compression chambers 20B with the second fixed scroll 4B, and the compression chamber 20B1 on the outermost peripheral side among these compression chambers 20B is shown in FIG. Thus, the inlet 9B of the fixed scroll 4B is always in communication. A seal member fitting groove 17B1 (groove) to which a contact seal 27 described later is attached is provided on the outer peripheral side of the back surface of the orbiting scroll 17B.
[0037]
An intermediate cooler 22 is provided between the first discharge port 10A and the second suction port 9B. The intermediate cooler 22 is constituted by a cooling device including, for example, a heat exchanger 23 and a fan 24. The pipes 25A and 25B are connected between the first discharge port 10A and the second suction port 9B. The intermediate cooler 22 cools the high-temperature discharged air discharged from the discharge port 10A through the pipes 25A and 25B, respectively, and guides it to the suction port 9B.
[0038]
Reference numeral 26 denotes a sliding contact ring provided on the outer peripheral side of the second fixed scroll 4B. The sliding contact ring 26 is formed in a flat ring shape from a metal material such as stainless steel. The sliding contact ring 26 is fitted into a ring mounting groove 4B1 provided on the flange portion 8B side of the fixed scroll 4B as shown in FIG. 2, and the surface thereof is a sliding contact surface with a contact seal 27 described later. Yes.
[0039]
A contact seal 27 is housed and mounted in a seal member fitting groove 17B1 (groove) of the second orbiting scroll 17B. The contact seal 27 includes a fixed scroll 4B on the high-pressure side and an orbiting scroll 17B on the high-pressure side. And the low pressure side of the outer peripheral chamber 40 are hermetically sealed. The outer peripheral chamber 40 is open to the atmosphere at a position (not shown) and is always at atmospheric pressure. The contact seal 27 includes an annular seal 28 as a seal member and annular leakage prevention rings 29 and 30 as first and second intrusion blocking seals. There are provided about six communication passages 31 at equal intervals in the circumferential direction through the annular seal sliding contact surface 28A, the seal member fitting groove bottom surface 17B2, and the annular seal bottom surface 28B facing the annular seal 28. The sealing device of the present invention includes an annular seal 28 as a sealing member, first and second intrusion blocking seals 29 and 30, a communication path 31, and an annular seal bottom surface 28B and the first and second intrusion blocking seals 29 and 30. And a back pressure chamber 32 as a sealed chamber formed by the bottom portion 17B2 of the seal member fitting groove 17B1.
[0040]
The annular seal 28 is formed as a seamless ring in the circumferential direction in order to hermetically seal between the fixed scroll 4B and the orbiting scroll 17B. Furthermore, an annular seal sliding contact surface 28A, which is one axial surface of the annular seal 28, is used as the sliding portion.
[0041]
The radial width h1 of the annular seal 28 is smaller than the radial width h2 of the seal member fitting groove 17B1 so that the annular seal 28 can be allowed to enter the seal member fitting groove 17B1 even when the annular seal 28 is thermally expanded. The gap is eliminated by disposing the leakage prevention rings 29 and 30 in the radial gap between the annular seal 28 and the seal member fitting groove 17B1.
[0042]
Further, the leakage preventing ring 29 enters the back pressure chamber 32 where the pressure in the outermost peripheral compression chamber 20B1 does not pass through the communication passage 31 and is directly formed between the seal member fitting groove 17B1 and the contact seal 27. To prevent.
[0043]
Here, the communication path 31 will be described in detail. The communication path 31 is formed as a path for introducing compressed air for pushing up the contact seal 27 toward the sliding contact ring 26 from the opening 31A on the annular seal sliding contact surface toward the opening 31B on the back pressure chamber 32 side. It is. The communication passage 31 is formed in the plurality of annular seals 28 and is configured to incline from the outermost compression chamber 20B1 on the high pressure side to the outer peripheral chamber 40 on the low pressure side, as shown in FIG.
[0044]
Reference numeral 33 denotes another seal member provided between the sliding surfaces of the low-pressure side fixed scroll 4A and the orbiting scroll 17A. The seal member 33 is a seal ring such as a face seal having a substantially rectangular cross section. Is formed. The seal member 33 may also be a seal similar to the contact seal 27.
[0045]
The scroll type air compressor according to the present embodiment has the above-described configuration. Next, the operation of the scroll type air compressor will be described.
[0046]
First, when the rotor 13 of the electric motor 11 is rotated, the rotating shaft 14 integrated with the rotor 13 performs a rotating motion integrally with the rotor 13. As a result of this rotational movement, the turning shaft 15 having the axis O 2 -O 2 performs a turning movement having a turning radius of the dimension δ within the rotating shaft 14 having the axis O 1 -O 1. Thereby, the orbiting scrolls 17A and 17B provided at both ends of the orbiting shaft 15 perform the orbiting operation with the orbiting radius of the dimension δ with respect to the fixed scrolls 4A and 4B.
[0047]
As a result, after the low-pressure compressed air compressed between the first fixed scroll 4A on the low-pressure side and the first orbiting scroll 17A is cooled by the intermediate cooler 22 from the discharge port 10A through the pipe 25A, It is led into the compression chamber 20B between the second fixed scroll 4B and the second orbiting scroll 17B from the suction port 9B of the second fixed scroll 4B on the high pressure side through the pipe 25B.
[0048]
The low-pressure compressed air that has flowed from the suction port 9B between the fixed scroll 4B and the orbiting scroll 17B is compressed again in the compression chamber 20B to become high-pressure compressed air, and a tank (not shown) from the discharge port 10B. And so on.
[0049]
Here, among the compression chambers 20B between the second fixed scroll 4B and the second orbiting scroll 17B, the outermost compression chamber 20B1 shown in FIG. 1 has a considerably higher pressure than the outside air. High-pressure compressed air in the outermost peripheral compression chamber 20B1 is likely to leak to the outside.
[0050]
However, in the present embodiment, as shown in FIG. 2, the seal member fitting groove 17B1 is provided in the second orbiting scroll 17B on the high pressure side, and the contact seal 27 is inserted into the groove 17B1, and the second The space between the sliding surfaces of the fixed scroll 4B and the second orbiting scroll 17B (sliding contact ring 26) is sealed.
[0051]
Then, the annular seal 28 slides with a pressing force f1 by guiding the compressed air in the outermost circumferential compression chamber 20B1 to the back pressure chamber 32 through the communication passage 31 provided in the annular seal 28 of the contact seal 27. Press against the contact ring 26.
[0052]
Here, the pressing force f1 will be described in detail with reference to FIG. FIG. 4 is a graph showing a pressure gradient with respect to the radial position of the annular seal sliding contact surface 28A, that is, a graph showing a pressure change introduced into the back pressure chamber 32 as a sealed chamber via the communication passage 31.
[0053]
In this graph, the pressure on the high pressure side is 0.4 MPa, the pressure on the low pressure side is 0.1013 MPa, an annular seal 28 having a width of 0.005 m (5 mm) is attached to the seal member fitting groove 17B1, and the one side member And the pressure gradient in the minute gap when the minute gap between the first member and the other member is 0.005 mm. The horizontal axis (passage length) corresponds to the length from the high pressure side end of the annular seal 28 to the high pressure side position 31A1 of the communication passage opening 31A. The pressing force f1 is the difference between the value (pressure in the back pressure chamber 32) indicated by this graph and the force acting on the annular seal sliding contact surface 28A that is pushed back from the sliding contact ring 26 side.
[0054]
The position 31A1 on the high pressure side of the communication passage opening 31A provided on the annular seal sliding contact surface 28A when new is located at a position that is only L1 away from the radial center side (high pressure side end). The pressure to be introduced is substantially close to the pressure in the outermost compression chamber 20B1, and the pressing force f1 at this time is the difference between the pressure in the back pressure chamber 32 and the force acting on the annular seal sliding contact surface 28A. Become.
[0055]
After the sliding movement for a certain period of time, as shown in FIG. 3, the annular seal 28 is worn, and its axial length becomes shorter than that of a new one. Since the communication path 31 is inclined to the annular seal 28, the position 31A1 on the high pressure side of the communication path opening 31A provided on the annular seal sliding contact surface 28A is from the radial center side (high pressure side). The pressing force f1 becomes weaker by the distance away from the outermost compression chamber 20B1 than when it is new.
[0056]
Here, the temporal change of the annular seal 28 will be described. When the scroll compressor 1 is new, the pressing force f1 is strong, and the annular seal sliding contact surface 28A is rapidly worn by the minute irregularities on the sliding contact surface 26A of the sliding contact ring and the annular seal sliding contact surface 28A. When a predetermined time elapses, both the contact surfaces of the annular seal slidable contact surface 28A and the slidable contact ring 26 come into contact with each other, and the pressing force f1 is reduced. Greatly reduced. In addition, since there is a minute unevenness on the contact surface of the annular seal contact surface 28A and the sliding contact ring 26 when it is new, there is a problem that the amount of leakage increases if the pressing force f1 is not large, but it has been used for some time. Thereafter, the contact surface of the annular seal contact surface 28A and the contact surface of the slidable ring 26 become familiar, and the pressing force f1 becomes small, and the wear almost stops at the place where the pressing force f1 becomes a force that does not wear the annular seal 28. Of course, wear due to long-term use continues, but the longer the wear is, the smaller the pressing force becomes, so that the service life is significantly extended compared to conventional seals.
[0057]
Also, the adjustment of the pressing force f1 is inclined to the annular seal 28 to provide the communication path 31, and the annular seal sliding contact surface 28A wears, thereby changing the position of the opening 31A of the annular seal sliding contact surface, and the pressing force f1. Therefore, durability can be enhanced while maintaining sealing performance with a simple configuration.
[0058]
Further, even when there are individual differences in the application devices due to processing tolerances, the wear almost stops at a place where the annular seal 28 does not wear for each application machine. Therefore, stable sealing performance can be exhibited.
[0059]
In the embodiment of the present invention, as a scroll type fluid machine, a scroll having a compression chamber at both ends of a drive shaft, compressed in one compression chamber, and then compressed to a higher pressure in the other compression chamber. A fluid-type fluid machine has been described as an example. However, the present invention is not limited to this. For example, the fixed side member including a casing, a fixed scroll provided on the casing and having a spiral wrap portion standing on the end plate, and the casing is rotatably provided. A driving shaft and a orbiting scroll provided on the front end side of the driving shaft so as to be pivotable and having a spiral wrap portion standing on the end plate so as to overlap the wrap portion of the fixed scroll and define a plurality of compression chambers; The present invention may be applied to a single-stage scroll fluid machine.
[0060]
In the embodiment of the present invention, a scroll fluid machine having compression chambers at both ends of a drive shaft, compressing in one compression chamber, and compressing to a higher pressure in the other compression chamber is taken as an example. explained. However, the present invention is not limited to this. For example, as shown in Japanese Patent Application Laid-Open No. 7-103151, the first and second components are arranged opposite to each other in the axial direction, and spiral end wrap portions are formed on the respective end plates. The fixed scroll and the fixed scroll are provided so as to be pivotable. A plurality of compression chambers are defined between the fixed scroll and the wrap portion of each fixed scroll. In a scroll type fluid machine constituted by a orbiting scroll in which a wrap portion is formed, the present invention may be applied while the fixed scroll and the orbiting scroll slide. Further, in a full-diameter rotary type scroll type fluid machine as disclosed in JP-A-9-133307, the present invention may be applied while two scrolls slide. Furthermore, even in a multistage scroll fluid machine that has a plurality of scroll fluid machines of the above two types and a general scroll fluid machine and compresses sequentially, the two scrolls of the high pressure side scroll fluid machine are slid. It may be applied while moving.
[0061]
In the embodiments of the present invention, the scroll air compressor is described as an example of the scroll fluid machine. However, the present invention is not limited to this. For example, the scroll fluid machine may be used as a vacuum pump. Applicable. In that case, the communication path 31 is configured to be provided with an inclined portion that is inclined from the outside air on the high pressure side toward the compression chamber on the low pressure side. By comprising in this way, the effect similar to the effect of this invention can be produced.
[0062]
In the embodiment of the present invention, as shown in FIG. 2, the communication path 31 is provided so as to be inclined from the vicinity of the outermost peripheral compression chamber 20B1 on the high pressure side toward the outside air on the low pressure side. However, the present invention is not limited to this, and any shape is acceptable as long as the position 31A1 on the high pressure side of the communication passage opening 31A gradually moves to the low pressure side as it wears. For example, as shown in FIG. However, the same effect as the present invention can be produced. In addition, as shown in FIG. 6, the same effect as that of the present invention can be obtained by forming the communication path 31 so as to be bent in a U shape so as to avoid the second intrusion blocking seal 30. Further, the opening 31B on the back pressure chamber 32 side of the communication passage 31 may be provided not only on the annular seal bottom surface 28B but also on one surface in the radial direction of the annular seal 28. However, in that case, it is set as a position in contact with the back pressure chamber 32 as a sealed chamber on one surface in the radial direction of the annular seal 28.
[0063]
In the embodiment of the present invention, as shown in FIG. 2, an O-ring fitting groove is provided on one surface in the radial direction of the annular seal 28, and the first and second intrusion blocking seals 29 are provided in the O-ring fitting groove. However, the present invention is not limited to this, and as shown in FIG. 7, the second intrusion-blocking seal 30 can adjust the pressure of the compressed fluid on the high-pressure side without providing a seal member such as an O-ring. By utilizing the annular seal member 28 against the groove 17B1, the second intrusion blocking seal may be formed. Further, the positions of the first and second intrusion blocking seals 29 and 30 may be provided on the annular seal bottom surface 28 </ b> B instead of the one surface in the radial direction of the annular seal 28. In that case, the annular seal 28 is fixed by a method such as adhering to the bottom surface 17B2 of the seal member fitting groove so that the first and second intrusion blocking seals 29, 30 do not move due to the pressure in the back pressure chamber 32. There is a need.
[0064]
Further, in the embodiment of the present invention, the case where it is applied to a scroll type fluid machine is described as an example of a type in which one axial surface of the annular seal 28 is used as a sliding portion. The same effect can be obtained even when the compressor is used in a compressor that generates compressed air by sliding movement. However, when one surface in the radial direction of the seal member is used as a sliding part, the diameter increases to keep the outer diameter or inner diameter equal to that of a new article when the seal member is worn by sliding movement, or It is necessary to use a seal member that shrinks. As a sealing member capable of expanding and contracting in the radial direction, a mouth seal is generally used. However, the mouth portion is devised so that the compressed fluid in the compression chamber 20B1 on the outermost peripheral side from the mouth portion is directly backed. It is necessary not to enter the pressure chamber 32.
[0065]
Further, in the embodiment of the present invention, the compressed fluid is supplied to the back pressure chamber 32 as the sealed chamber via the communication path 31 and the contact seal 27 is pressed against the mating surface, so the sliding motion is started. Then, the contact seal 27 is not pressed against the mating surface until the compressed fluid is supplied. However, by using a seal having a large frictional force such as a rubber O-ring as the first and second intrusion blocking seals and capable of regulating the position of the annular seal 28, the sliding motion is stopped and the pressure in the sealed chamber is reduced. Since the annular seal 28 remains in contact with the other member even if the pressure decreases, the leakage of the compressed fluid immediately after starting the sliding motion can be prevented.
[0066]
【The invention's effect】
  As detailed above,In the present invention, according to the wear of the seal member, the high pressure side end of the opening of the communication path will move to the low pressure side, the pressure of the sealed chamber is reduced, and the pressing force can be reduced,The optimum pressing force can be obtained. Therefore, sliding resistance can be suppressed, wear of the seal member can be reduced, and durability can be improved.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a scroll type air compressor according to an embodiment of the present invention.
FIG. 2 is an enlarged vertical sectional view of a main part showing an a part in FIG. 1 in an enlarged manner. (When new)
FIG. 3 is an enlarged vertical sectional view showing a main part of a part a in FIG. 1; (After using for some time)
FIG. 4 is a graph showing a pressure gradient with respect to a radial position of an annular seal sliding contact surface 28A according to an embodiment of the present invention.
FIG. 5 is a cross-sectional view of the annular seal 28 when a position 31A1 on the high pressure side of the opening 31A of the communication passage 31 is formed in a stepped manner as another embodiment of the present invention.
FIG. 6 is a cross-sectional view of an annular seal 28 when a communication path 31 is formed in a U shape as another embodiment of the present invention.
7 is a cross-sectional view of the annular seal 28 when a second intrusion blocking seal 30 is formed by the groove 17B1 and the annular seal 28 as another embodiment of the present invention. FIG.
[Explanation of symbols]
4B Fixed scroll (other side member)
6A, 6B, 19A, 19B Wrap
17B orbiting scroll (one side member)
17B1 Sealing member fitting groove (groove)
28 Annular seal (seal member)
29 First intrusion blocking seal
30 Second intrusion blocking seal
31 passage
31A1 Opening at the high pressure side end of the communication path
32 Back pressure chamber (sealed chamber)

Claims (6)

One side member;
The other side member arranged to face the one side member and slidingly moves;
A sealing device provided between the one side member and the other side member and defining a high pressure side and a low pressure side;
A groove provided on the sliding surface of the one side member;
A sealing member inserted into the groove;
A first intrusion blocking seal that is provided between the seal member and the groove and blocks intrusion of pressure on the high pressure side;
A second intrusion blocking seal that blocks intrusion of pressure on the low pressure side;
A sealed chamber formed by the first and second intrusion blocking seals, the groove bottom side and the seal member;
A communication path provided in the seal member so as to communicate the sealed chamber side and the sliding portion side of the seal member;
The said communication path is comprised so that the high voltage | pressure side edge part of opening of the said sliding surface side may be moved to the low voltage | pressure side according to abrasion of the said sealing member . The sealing device according to claim 1 , wherein an inclined portion that is inclined from the high pressure side to the low pressure side is provided in the communication path from the sliding surface side toward the sealed chamber. The sealing member is an annular seal assembly as claimed in claim 1 or 2, characterized in that a sliding surface of one axial side of the seal member.   One side member;
  The other side member arranged to face the one side member and slidingly moves;
  A sealing device provided between the one side member and the other side member and defining a high pressure side and a low pressure side;
  An annular groove provided on the sliding surface of the one side member;
  An annular seal member that is inserted into the groove and has one axial surface in sliding contact with the other side member;
  A first intrusion blocking seal that is provided between the seal member and the groove and blocks intrusion of pressure on the high pressure side;
  A second intrusion blocking seal that blocks intrusion of pressure on the low pressure side;
  A sealed chamber formed by the first and second intrusion blocking seals, the groove bottom side and the seal member;
  A communication path provided in the seal member so as to communicate the sealed chamber side and the sliding surface side of the seal member;
  The sealing device according to claim 1, wherein the communication path is provided with an inclined portion inclined from the high pressure side to the low pressure side from the sliding surface side toward the sealed chamber. A scroll type fluid machine that compresses fluid sucked from outside during a swiveling motion by forming a compression chamber by overlapping the lap portions of two scrolls,
A scroll type fluid machine using the seal device according to any one of claims 1 to 4 as a seal device provided between the two scrolls and defining a compression chamber with the outside. A multi-stage scroll type fluid machine that has a plurality of scroll type fluid machines and compresses sequentially,
A multi-stage scroll type fluid machine using the scroll type fluid machine according to claim 5 in the second and subsequent stages of the multi-stage scroll type fluid machine.

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